With the development of science and technology, various high-tech means find widespread applications in the field of monitoring a target person.
The current technology of monitoring a target person is a video monitoring technology, which monitors the target person by placing cameras at places such as main traffic accesses and entrances and exits of buildings. However, cameras are prone to be obstructed by objects such as trees and advertisement boards. Meanwhile, when a target person enters a building (such as a house, an office or a restaurant), the cameras are unable to acquire images of the target person, and therefore the monitoring cannot continue, which easily results in monitoring failure.
Therefore, the current technology of monitoring a target person cannot achieve continuous monitoring.